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Flexible anisotropic magnetoresistive sensors for novel eddy current testing applications
No full textThe standard method for eddy current testing (ET) of conductive materials relies on using rigid coils. In recent years magnetoresistive (MR) sensors in combination with an excitation wire have become a promising candidate for this application since it would increase the spatial resolution. New developments in flexible electronics have enabled the production of flexible sensors with the novel capability of scanning samples in conformal contact with the surface. In this article flexible anisotropic magnetoresistive (AMR) sensors were used in combination with a thin induction wire to perform eddy current testing of a curved aluminum sample with several defects imprinted on its surface. To benchmark the performance of this new method, a flat sample with reference defects of various dimensions was also scanned using flexible AMR sensors, inductive coils and rigid giant magnetoresistive (GMR) sensors. The results show that this new method of using flexible magnetic field sensors coupled with an excitation wire can easily be applied to the scanning of curved samples, while in the benchmark test employing the flat sample, the performance is not far behind more conventional techniques, with defects with depths down to 30 μm and widths down to 400 μm being detectable with an SNR of 3 (signal magnitude) and 8 (signal phase shift) at the excitation frequency of 50 kHz, and defects with depths down to 30 μm and widths down to 600 μm being detectable with an SNR of 10 (signal magnitude) and 17 (signal phase shift) at 260 kHz
Circular Economy - Einführung in die Umsetzung
No full textDer Vortrag fasst die internationalen, europäischen und nationalen Entwicklungen zur Transformation der linearen hin zu einer zirkulären Wirtschaft zusammen. Auf den drei Ebenen folgt der Vortrag jeweils der selben Logik: (i) Bedarfe, (ii) Strategien und Pläne sowie (iii) konkrete Maßnahmen. Ebenfalls werden Hinweise zu weiteren Informationsquellen gegeben
Combining passive and active ultrasonic stress wave monitoring for the characterization of the early-age properties of a UHPFRC beam
No full textThis article focuses on the characterization of the early-age properties of Ultra-High-Performance Fiber-Reinforced Cementitious Composite (UHPFRC), which is becoming popular for designing lightweight and durable structures. Due to the large proportion of cement in the mix, the hardening of UHPFRC is significantly faster than conventional concrete. Therefore, the development of UHPFRC properties, such as the elastic modulus, is difficult to monitor as it happens while elements are within the formwork. For this reason, the hydration process of UHPFRC elements is not fully understood yet. A combined passive (or acoustic emission) and active ultrasonic stress wave monitoring approach has the potential to characterize structures made of cementitious materials over their entire service duration. Using a network of embedded ultrasonic transducers, monitoring can start only a few instants after casting. A UHPFRC beam with a T-shaped cross-section and a length of 4.2 m was constructed and instrumented with 24 transducers as well as 15 thermocouples. Monitoring results lead to the characterization of the development of the early-age UHPFRC properties on the structural-element scale while the specimen is within the formwork. The continuous monitoring approach enabled accurate estimations of the spatial and temporal evolution of the modulus of elasticity. Thanks to this novel combination of monitoring techniques, the early age properties of UHPFRC, which were measured at the material scale, are confirmed at the structural scale for the first time
Plasmaschallwandler - mögliche Zukunft der luftgekoppelten zerstörungsfreien Prüfung
No full textPlasma-Mikrohohlkathoden-Wandler bieten eine neuartige Methode für die luftgekoppelte zerstörungsfreie Prüfung (ZfP) mit der besonderen Fähigkeit, Ultraschallwellen über einen breiten Frequenzbereich anzuregen. Durch den Einsatz von ionisiertem Gas als Wellenerzeugungsmedium ermöglichen diese Wandler einen effizienten, berührungslosen Betrieb ohne die Notwendigkeit von Kopplungsmitteln.
Diese Vorstudie konzentriert sich auf die Charakterisierung des grundlegenden Verhaltens und der Leistung von Plasma-Mikrohohlkathoden-Wandlern als potenzielle Ultraschallwandler für ZfP-Anwendungen. In ersten Experimenten werden Laservibrometrie-, Thermosonden- und Kraftsondentechniken eingesetzt, um die Erzeugung, Ausbreitung und Erkennungsfähigkeit akustischer Wellen in einer Reihe von Materialien und Geometrien zu bewerten. Die ersten Ergebnisse zeigen, dass Plasmaschallwandler in der Lage sind, breitbandige Ultraschallwellen anzuregen, und lassen auf ihr Potenzial für die Materialcharakterisierung und Fehlererkennung schließen.
Obwohl sie sich noch in einem frühen Entwicklungsstadium befinden, sind Plasma-Mikrohohlkathoden-Wandler vielversprechend für die Weiterentwicklung der luftgekoppelten zerstörungsfreien Prüfung. Zukünftige Arbeiten werden sich mit der Optimierung des Wandlerdesigns befassen, um eine höhere Effizienz und die Integration in praktische Prüfsysteme zu erreichen. Diese Studie bietet eine Grundlage für das Verständnis der potenziellen Auswirkungen der Plasma-Mikrohohlkathodentechnologie und ihrer Rolle bei der Gestaltung der nächsten Generation von ZfP-Verfahren
QI Digital: Cross-Location IT Infrastructure and Asset Administration Shell as a Digital Twin
No full textIm Rahmen der von der BAM und anderen Partnern ins Leben gerufenen Initiative „Digitale Qualitätsinfrastruktur“ liegt der Fokus u.a. auf der Entwicklung von neuen Zertifizierungsworkflows. Dabei ist eine besondere Bedeutung dem Zusammenführen von Operational Technology (OT) und Informationstechnik (IT) beizumessen. Zur Datenintegration aus der Sensor-Feldebene einer Versuchs-Wasserstofftankstelle wurde eine solche Infrastruktur zunächst in einer Laborumgebung aufgebaut.
Dieser Vortrag beschreibt die Implementierung des standardisierten und von der Plattform Industrie 4.0 empfohlenen digitalen Zwillings "Verwaltungsschale" an dieser Wasserstofftankstelle. Außerdem wird die Implementierung einer standortübergreifenden IT-Infrastruktur über VPN/5G beschrieben
Einteilung Explosivstoffe & Pyrotechnik, Sonderthemen
No full textEs werden die Eingruppierungskriterien von zivilen Explosivstoffen, deren Wirkungsweisen und Zusammensetzungen und ausgewählte Sonderthemen im Bereich Pyrotechnik vorgestellt
Spectrally resolved lithium isotope quantification through high-resolution spatial heterodyne spectrometry
No full textIsotope ratio determination of lithium is increasingly important in fields ranging from geochemistry to battery diagnostics. While mass spectrometry remains the gold standard, it is costly, cumbersome, and incompatible with portable or inline implementations. Optical emission spectroscopy presents an appealing alternative. However, it is traditionally limited by insufficient spectral resolution or resolving power to separate lithium isotope emissions due to their generalized designs for a wide spectral range; this often requires overly complicated algorithms to overcome the instrumental drawbacks. (79)
Results Here, we report a high-resolution optical method for lithium isotope quantification using a custom-built spatial heterodyne spectrometer (SHS) combined with a reduced-pressure glow discharge source. This configuration yielded a resolving power of 189,000 and enabled baseline resolution of lithium d-line emission features even without the need for preliminary data processing. Despite the inherent low sensitivity of SHS, a detection limit of 30 pmol was achieved using a standard industrial camera. To improve quantitative accuracy, we introduced a deconvolution-based spectral lineshape recovery technique alongside a bootstrapping-based error propagation strategy. These methods facilitated robust isotope ratio calibration using both peak-height and peak-area metrics. The SHS platform additionally enabled the determination of relative transition probabilities, suggesting the feasibility of calibration-free operation.
This work demonstrates the practical viability of SHS for high-specificity, high-resolution lithium isotope analysis. The approach is compact, potentially field-deployable, and adaptable to other elements with optically resolvable isotope shifts, offering a route toward accessible and calibration-free optical isotopic analyses
How thermographic NDT can contribute to achieving the Sustainable Development Goals
No full textIn 2015, the global community adopted the UN 2030 Agenda - a roadmap for the future. The Agenda covers economic, environmental and social aspects of development. They formulated the so-called 17 Sustainable Development Goals (SDGs). And what it means is: We are facing a profound systemic transformation! But the question is: how can we achieve these goals? Of course, each of us can contribute by changing some of our habits. But for us as a research organisation, the answer must be science! There are a number of key technologies that will be needed to manage this change. Our contribution as the NDT community should be to support this global transformation by making it a safe one! And infrared thermography is an integral part of this NDT community and represents one of these key technologies.
Of the 17 SDGs, we have identified five SDGs (Goal 7: affordable and clean energy, Goal 9: industry, innovation and infrastructure, Goal 11: sustainable cities and communities, Goal 12: responsible consumption and production, Goal 13: climate action) that we believe we can support in line with our mission. In this paper, four specific examples from BAM (Bundesanstalt für Materialforschung und –prüfung / German Federal Institute for Materials Research and Testing) will be used to show how thermographic NDT can contribute to the achievement of the SDGs. As a first example, we want to establish the quality control of novel, resource-conserving high-temperature additive manufacturing processes by establishing thermography-based in-situ measurement techniques. The aim is to achieve zero-defect manufacturing for all processes involving heat, such as the PBF-LB/M and DED-LB/M processes, which are currently entering industrial mass applications. As a second example, our research is focused on replacing traditional resource-intensive inspection methods such as liquid penetrant or magnetic particle inspection with robotic high-resolution laser thermography, which we call photothermal CT and which will enable fully automated inspection of complex geometries at high speed and high resolution. As a third example, we want to support the energy transition and climate protection as a whole through modern IRT inspection techniques by establishing thermographic inspection of wind turbines, in particular of rotor blades. Such inspections will make wind energy safer to use, enable longer operating times and make it more economical by improving its efficiency. In addition to industrial applications, IRT inspection techniques can be applied to the civil engineering sector to support sustainable infrastructure. Useful application scenarios include the early detection of corrosion under protective coatings and the inspection of concrete coatings found on parking decks, which are mainly applied by hand
A Framework for Transforming Process Control System Data from a Hydrogen Fueling Station into HyCReD Data
No full textReliability data for hydrogen infrastructure components is essential for developing Quantitative Risk Assessment (QRA) for these technologies, which in turn is necessary for a safer deployment and expansion of the hydrogen market. However, there is currently a lack of hydrogen component reliability data available for these systems, thus limiting the usefulness of insights obtained from these QRA. The Hydrogen Component Reliability Database (HyCReD) has been proposed as a tool for reliability data collection and as a source for future QRAs. In this paper, we develop a digital tool that automatically processes data coming from Process Control System (PCS) in a hydrogen fueling station, detects the relevant failure events for hydrogen systems during its operation, and then logs the event information into HyCReD. To build this tool, we first categorized the station components in hydrogen service, their specific failure modes, and the specific failure mechanisms that are relevant to a QRA. Then, we identified the data available in the station PCS and the methods available for diagnosing the relevant failure events. The resulting tool is divided into three steps: (1) PCS data collection through an API, (2) data analysis for the detection and diagnosis of new failure events, and (3) logging that event into HyCReD. Finally, we discuss the potential for expanding the detection and diagnosis to more complex failure modes present in a hydrogen fueling station. This digital tool is set for implementation and validation on an experimental hydrogen fueling site. The goal for this digital tool is to be applicable to every kind of hydrogen fueling station and to be extendable to similar hydrogen technologies
Settling Velocities of Tire and Road Wear Particles: Analyzing Finely Graded Density Fractions of Samples from a Road Simulator and a Highway Tunnel
No full textThe terminal settling velocity is considered the most critical parameter determining the transport of tire and road wear particles (TRWP) in aquatic environments. Nonetheless, no respective empirical data has been reported so far. In this study, particle samples from a road simulator and a highway tunnel were investigated with a validated imaging method. Different density and size fractions of both samples were measured separately, acquiring sizes and settling velocities of more than 30,000 individual particles. In addition, tire marker polymers were analyzed for each fraction via thermal extraction desorption-gas chromatography/mass spectrometry. Finally, the acquired particle data was combined according to the fractions’ estimated tire contents in order to deduce detailed probability distributions of particle size and settling velocity for the actual TRWP from both samples. Weighted by TRWP-incorporated tire mass, median diameters of 54 and 44 μm as well as median settling velocities of 0.65 and 0.22 mm/s were found for TRWP from the road simulator and highway tunnel, respectively. This study thus provides the first ever empirical data on TRWP settling velocities in water, which can be highly valuable input for modeling the environmental transport of TRWP and for dimensioning TRWP retention systems